Product selectivity in plasmonic photocatalysis for carbon dioxide hydrogenation

• Published in: Nature communications Vol. 8; no. 1; pp. 14542 - 9
• Main Authors: Zhang, Xiao, Li, Xueqian, Zhang, Du, Su, Neil Qiang, Yang, Weitao, Everitt, Henry O., Liu, Jie
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 23.02.2017; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 639/638/77/887; 639/638/77/890; 639/925/357/354; Carbon dioxide; Carbon monoxide; Catalysis; Chemical reactions; heterogeneous catalysis; Humanities and Social Sciences; Hydrogenation; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Light; Light intensity; MATERIALS SCIENCE; Methane; multidisciplinary; Nanoparticles; Photocatalysis; Rhodium; Science; Science (multidisciplinary); Ultraviolet radiation; North Carolina; United States > US
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms14542

Photocatalysis has not found widespread industrial adoption, in spite of decades of active research, because the challenges associated with catalyst illumination and turnover outweigh the touted advantages of replacing heat with light. A demonstration that light can control product selectivity in complex chemical reactions could prove to be transformative. Here, we show how the recently demonstrated plasmonic behaviour of rhodium nanoparticles profoundly improves their already excellent catalytic properties by simultaneously reducing the activation energy and selectively producing a desired but kinetically unfavourable product for the important carbon dioxide hydrogenation reaction. Methane is almost exclusively produced when rhodium nanoparticles are mildly illuminated as hot electrons are injected into the anti-bonding orbital of a critical intermediate, while carbon monoxide and methane are equally produced without illumination. The reduced activation energy and super-linear dependence on light intensity cause the unheated photocatalytic methane production rate to exceed the thermocatalytic rate at 350 °C. Atmospheric CO 2 can be transformed into valuable hydrocarbons by reaction with H 2 , but CO is the favoured kinetic product. Here, Liu and co-workers show that plasmonic rhodium nanoparticles not only reduce the activation energy for CO 2 hydrogenation, but also photo-selectively produce methane.